Haematopoietic System ( 5% ) Flashcards
1
Q
- A man with type B blood
- (a) has the commonest blood type
- (b) cannot have a child with O type blood
- (c) cannot have a child with AB type blood
- (d) cannot have a child with type A
- (e) none of the above is true
A
- (a) has the 2nd rarest blood type
- O 45%, A (41%), B (10%), AB (4%)
- (b) can have a child with O type blood
- If mother is OO and he is OB (Mendelian genetics)
- (c) can have a child with AB type blood
- Mother is AA or AB
- (d) can have a child with type A
- Mother is AA or AB
- (e) none of the above is true
2
Q
- Thrombocytopaenia
- (a) occurs commonly in HIV
- (b) causes spontaneous bleeding at levels of 90,000/μL
- (c) occurs with hyposplenism
- (d) is related to platelet survival in PND
- (e) is not associated with megaloblastic anaemia
A
-
(a) occurs commonly in HIV
- Most common haematologic manifestation of HIV
- (b) causes spontaneous bleeding at levels of 20,000/μL
- (c) occurs with hypersplenism
- Hyposplenism causes thrombocytosis
- (d) is related to platelet survival in PND
- (e) is associated with megaloblastic anaemia -> causes poor development and increased destruction of megakaryocytes
- Thrombocytopaenia caused by
- decreased production (aplastic anaemia, leukaemia, B12 deficiency),
- decreased platelet survival (immune targets IIb-IIIa; non-immune prosthetic heart valves, hypertension),
- increased consumption,
- dilution (massive transfusion), or
- sequestration (spleen)
3
Q
- Myelofibrosis
- (a) causes leukoerythroblastic anaemia
- (b) causes a decrease in megakaryocytes
- (c) stimulates erythropoietin production
- (d) is ameliorated by extramedullary haematopoiesis
- (e) causes hyposplenism
A
Not sure, no answer given, all except e) seem correct so maybe the question is worded wrong, or im an idiot who cant be bothered opening R&C right now.
- (a) causes leukoerythroblastic anaemia
- Leukoerythroblastic anemia describes the presence in the peripheral blood of nucleated erythrocytes and immature white cells of the neutrophilic myeloid series
- (b) causes a decrease in megakaryocytes
- Causes pancytopenia due to medullary fibrosis, which should also displace megakaryocytes
- (c) stimulates erythropoietin production
- Would be expected in anaemia, and is what drives the extramedullary haematopoiesis
- (d) is ameliorated by extramedullary haematopoiesis
- Also seems true, this also occurs at least (but doesn’t completely ameliorate it)
- (e) causes hypersplenism
4
Q
- Regarding Rhesus incompatibility (2006)
- (a) 50% of Caucasians are rhesus positive
- (b) requires CDE to be positive (requires absence of CDE to be negative, 2006)
- (c) there are low levels of autoantibodies to AB
- (d) anti D is most antigenic
- (e) Agglutinins rarely occur spontaneously
A
a) 85% of caucasians are positive
b) Only requires D to be positive (the most potent antigen and what they test for)
c) Rh has seperate antigens to AB system
d) D is the most antigenic, anti-D is the IgG used to prevent further production of Ig
e) Agglutinins are the antibodies, agglutinogens are the antigens (A, B, Rh etc). Intestinal bacteria have similar antigens so ABO agglutinins are formed soon after birth, however they do not develop towards Rh until exposure (eg birth)
They have said d) for this question, however e) seems more correct
5
Q
- Macrocytic [megaloblastic] anaemia occurs in all the following conditions EXCEPT (2000)
- (a) pregnancy
- (b) folate/vitamin B12 deficiency
- (c) EBV infection
- (d) neoplasm
- (e) hyperthyroidism
A
- (a) pregnancy (causes folate and/or B12 deficiency)
- (b) folate/vitamin B12 deficiency is the cause of megaloblastic anaemia
- (c) EBV infection not on table
- (d) neoplasm (causes folate and/or B12 deficiency)
- (e) hyperthyroidism (B12 deficiency)
6
Q
- Non-thrombocytopaenic purpura is associated with
- (a) aplastic anaemia
- (b) SLE
- (c) meninococcaemia
- (d) HIV
- (e) EBV
A
c) Meningococcaemia
Also: drug reactions (drug induced antibodies, leading to vascular deposition of antibody), scurvy and Ehlers-Danlos syndrome, Cushings syndrome, HSP (IgA), amyloid
Aplastic anaemia causes a thrombocytopenic purpura
7
Q
- Which cell type is found predominantly in the periarteriolar sheaths in the white pulp of the spleen? (2004)
- (a) B lymphocytes
- (b) Neutrophils
- (c) Mast cells
- (d) T lymphocytes
- (e) Macrophages
A
(d) T lymphocytes
B lymphocytes are in intervals of lymphatic sheath expansions of lymphoid nodules on one side of the artery
8
Q
- Iron deficiency results in
- (a) increased serum ferritin
- (b) decreased transferrin saturation
- (c) decreased total iron binding capacity
- (d) reduction in skin shedding and therefore iron loss
- (e) decreased transferrin levels
A
(b) decreased transferrin saturation
- Low serum iron causes the body to produce more transferrin to try and mop up any spare iron. Thus transferrin rises whilst serum iron levels drop, so saturation will reduce*
- In anaemia of chronic disease, transferrin saturation is reduced, as the TIBC and serum iron are reduced equally (so percent saturated is the same), whilst ferritin (iron storage) is increased, presumably to try and keep active iron away from infetive organisms which may use it.*
9
Q
- Regarding iron metabolism (?2004, 2006)
- (a) Iron excretion is tightly regulated
- (b) Iron absorption is increased by ascorbic acid
- (c) 2% of heme iron is absorbed
- (d) Ferritin is found only in the liver, spleen and bone marrow
- (e) none of the above is true
A
(b) Iron absorption is increased by ascorbic acid
- (a) Iron absorption is tightly regulated
10
Q
- Regarding iron which of the following is incorrect (?2004)
- (a) absorption is increased by ascorbic acid
- (b) most is found in myoglobin
- (c) most is absorbed in the duodenum
- (d) women have smaller iron stores than men
- (e) transferrin is usually 33% saturated
A
(b) most is found in haemoglobin
- (a) absorption is increased by ascorbic acid
- (c) most is absorbed in the duodenum
- (d) women have smaller iron stores than men
- (e) transferrin is usually 33% saturated
